1. Field of the Invention
The present invention relates to agricultural machines and more particularly to a harvesting machine comprising a frame movable in relation to the ground along rows of standing plants, members for picking up the crop from said plants, and at least two conveyors for transferring the crop towards the interior of the machine.
2. Description of the Prior Art
In hitherto known machines of this type, notably grape-gathering machines, sealing members and crop transfer members, such as automatic conveyors, are provided. As a rule, in machines of the above-defined type the sealing members consist of inclined surfaces disposed on either side of the row of plants and fixed in translation in relation to the machine.
Each sealing surface, consisting either of a flexible longitudinal strip or belt, or of a series of rigid retractable plates, engages with its inner edge the lower portion of the plant foot or stem, its outer edge being disposed at a lower level in the vicinity of an automatic conveyor equipping the machine.
The crop gathered from the plants by the corresponding members of the machine, such as beaters, shakers or whips, and more particularly the grapes detached from the vine, drop partially upon said surfaces and slide thereon until they reach one of the conveyors which transfers the crop to a discharge place. As a rule, these conveyors consist of casings in which endless belts are caused to circulate continuously.
These two known systems are attended by the same, multiple inconveniences.
It is obvious that these systems on the one hand cause a permanent wear and tear of the sealing surfaces due to the continuous frictional contact between these surfaces and the lower portion of the plants, and on the other hand have considerable vertical and horizontal dimensions due to the superposition and juxtaposition of the sealing members and transfer members, the latter having in addition a substantial height as a consequence of the superposition of the two runs of the endless belts or like elements.
Moreover, the use of two flexible bands as sealing surfaces is attended, on either side of the fixed obstacles consisting for example of vine-plants, by the formation of longitudinal areas of relatively great amplitude separating the two belts, thus creating particularly detrimental untight spots.
Finally, the construction of sealing surfaces in the form of rigid retractable plates resiliently urged to their closed position and opening when engaged by fixed obstacles is attended by other specific inconveniences, notably a certain complexity and a relatively high cost, with a poor reliability in service due to the distortions and breakages likely to occur in case of fierce shocks against fixed obstacles, a considerable risk of damaging the stems of plants and the impossibility, for a machine engaged along a row of plants, of reversing due to the one-way mode of operation of the plates.